The invention relates to a fuel injection pump of the type disclosed, for example, in U.S. Pat. No. 2,565,681, and German published application No. 2,146,797.
In the noted U.S. Patent, the top portion of the cylindrical sleeve and the annular screw are arranged one behind the other, thus increasing the overall height of the injection pump in a disadvantageous manner.
In order to measure the pre-stroke, that is the travel of the pump piston from its bottom dead center position until it closes the control bore and the delivery stroke commences in the injection pump disclosed in the noted German published application, the pressure valve fitted in the extension of the pump piston, and the associated pipe connection have to be removed in order to be able to apply the feeler pin of a pre-stroke measuring device to the end face of the pump piston. This method is necessary particularly when the associated pump housing does not offer the possibility of intervention for a measuring device in the region of the pump piston drive, or when the injection pump is in the form of a plug-in pump and is plugged into the engine housing, so that, here also, the pre-stroke can only be measured on the pump piston.